Mold for casting clutch and transmission gearing casings



A. A. BULL MOLD FOR CASTING CLUTCH AND TRANSMISSION GEARING CASINGS Filed March 1, '1922 Ill ,4

11f Wow Patented Aug. 19, 1924.

ARTHUR A. BULL, 0'35 DETROZT, MICHIGAN AS SIGNOE TOJGENERAL MOTORS CORPORA- TION, OE" DETR'QIT;LWIICHIGAN, A CORPORATION OF DELAWARE.

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MOLD FOR CASTING CZU'TGH AND TRANSLTISSION, GEARING CASINGS. I

Application filed March 1, 1922 Serial No. 540,120.

To all whom it may concern:

Be it known that l, a citizen of the United States of America and a resident of Detroit county of Wayne, and State of Michigan, have in-- vented certain new and useful lmpmve ments in Molds tor Casting Clutch and Transmission Gearing Casings. of which the following is a toll, clear, concise and exact description, such as will enable others skilled in the art to which the invention relates to make and use the same, reference being made therein to the accompanying drawings. which form a part of this specification. a

My invention relates to the art. of casting articles from molten metal in sand molds, and particularly to the art of casting integral or single piece casings for use inthe power plants of motor driven vehicles op erated by internal combustion engines and within which casing the change speed transmission gearing and the clutch and flywheel of the engine are housed; said casings being of hollow construction, and having an open end which idapted to be fastenedto the engine casingat the end thereof where the :ly wheel is located. i

More specifically considered, my inven tion contemplates and the principal object thereof is to provide an improved mold for use in producing single piece combined clutch and transmission gearing casings by the use of which the casing. may be cast in a vertical position; the mold requiring a flask comprising two parts only and the same being made up of three green sand parts or sections and without the use o't' dried. out and baked cores such as have heretofore been commonly used in the pro duction of similar casings. One part of the mold employed is for convenience of. expression referred to hereinafter as a core and. while said part has various of the characteristics of a core as that term is commonly used in the metal founding art the same may be made from green sand and does not have to possess the strength ordinarily inherent in cores and necessary therein when they are supported from their ends and in a horizontal. position, ashas heretofore commonly been the case in producing casings of the general type to which invention relates. p

A tlfurther advantage following from the ARTHUR i4. BULL,

.thereol use of a two'part flask in theproduction of a complete casing is thatmuch less foundry floor space is required than has hereto: forebeen necessaryv whensimilar casings have been cast intwo parts; and much less sand is obviously required when a complete casing is formed by the use of two flask sections only than isnecessary when the cas ing; is ,made in .two parts each requiring a separate flask comprising at least two parts and, commonly, a core for each flask. 1 Another advantage secured by the.;use of my invention is that the molding operations are greatiy simplified as the simplest possible form of flask is employed; andno carefully performed core setting operation is involvedcin the assembling of the mold preparatory to pouring the molten metal thereinto in the castmg operation.

Although as regards various of its aspects my invention mayproperly be. consideredas an improved process for producingsingle piece combined clutch and transmission or change, speed gearing. casings the same is herein described and claimed asan improved mold for use in producing such devices; it

being appreciated, however, that my invention includes all such variations and modifications of the particular embodiment 5 illustrated and hereinafter described as come within the scope of the coneluding claims.

In the drawing accompanying and forming a part of'this specification and wherein the preferred embodiment of my invention is illustrated:

Figure lis a sectional View upon a vertical central plane'show-ing'a mold made in accordance with my invention completely assembled, and fluid metal poured thereinto to form a casing. I

FigureQis a, view showing a section upon a horizontal plane indicated by the line 22, Figure 1. I i

Figure 3 is a similar View upon a plane indicated by the line 3+3, Figure 1.

Figure 4; isa sectional view similar to Figure l showing the lower mold section only, and the coresupported uponthe upper end thereof, 7

Figure is a similar View showing both the lower and upper mold sections as they arebeing assembled to close and complete themol. I f

Referring now to the drawing the referill) , tion, or by other approved mold making ence numeral 6 designates the lower part of a two-partflask used in my invention and which contains and forms a part of a lower mold section made from green sand, and having an upwardly extending portion 7 shaped to conform with a part of the m terior of the casing to be produced; the form of such projecting portion in the embodiment of my invention illustrated being such as to provide the clutch chamber of the casing produced when molten metal is poured into the completed mold. The lower mold section may be produced by filling the flask section with sand while it rests bottom side up upon a match. plate or board having a recess conforming with the said projecmethods, as will be appreciated.

Resting upon and supported by the portion 7 and forming in effect a part of the lower mold section is a core 8 formed also preferably from green sand as by the use of a suitable core box; but which core does not have to be baked as in the case of ordinary cores, nor to be made from materials nor in a manner such that it will have the strength commonly inherent in cores for foundry use. This core is supported by the projecting portion 7 as will be seen, and is commonly spaced apart from the upper end thereof as shown at 9 in Figure l, so as to provide for a transversely extending web within the casing produced during the casting operation;

the form of the upper surface of the portion 7 and of the adjacent lower surface of the corebeing such as to provide for bearings in the said web in which the various shafts, rods and other elements of the change speed. gear mechanism when assembled within the casing are supported at one end, as will be understood. The core 8 in the embodiment of my invention illustrated is of a form 'such as to provide the change speed gear chamber of the casing produced, and the upper end'thereof is spaced apart from the confronting inner surface of the upper section of the mold to be hereinafter described; to thereby provide a transversely extending end wall of the finished casing, and which wall carries bearings for the other ends of the shafts of the change speed gearing designed to be assembled within the chamber formed by said core.

This core, being comparatively massive and of dimensions approaching uniformity in all directions, that is having no portion of greatly reduced cross section as compared to that of the main portion of the core; may by the use of modern molding machines be so formed as to have very considerable strength as compared with a hand formed Y and rammed core; and may by the exercise of reasonable care in handling be removed. from the core box used in its formation and transferr'ed to the lower section of the mold of which it is to form a part. As a matter of fact large numbers of clutch and transmission casings have been cast in molds thus formed and in accordance with my invention, and without the exercise of any faculty on the part of the molder other than ordinary care in forming, handling and setting the core. It will be appreciated, however, that if strength in the green sand core contemplated in excess of that ordinarily inherent in such cores is required a strengthening rod or rods, a cage or spider construction,'or equivalent skeleton structure may be embodied in the core during the formation thereof, these being methods and expedients well known to those skilled in the art to which my invention relates.

In order that the core 8 may be more firmly supported by and above the projecting portion 7 and properly spaced from the interior of the upper mold section the said projecting portion is provided with a depression or recess 10 in its upper surface, and the core 8 with a projection 11 extending into said recess; this construction acting to steady the core and to determine the position thereof relative to the said projection and to the upper mold section to be next described. This projection also acts to provide an opening in the transverse internal wall or web of the casing produced by spacing the core above the projection, as hereinbefore explained, and within which opening the main bearing of the transmission gearing is supported when the casing is in use. The recess 10 is preferably lined with a thin sheet metal cup 12 embedded in the upper end thereof during the formation of the lower mold section, so that the recess which receives the projection 11 can be wiped out without injuring the walls thereof should sand fall thereinto, preparatory to the final placing of the core 8 in place upon the lower portion of the mold.

The reference numeral l3 designates the upper part of the two-part flask used in my invention and which contains the upper mold section 14 which is made also of green sand,

and which is hollow in form and shaped so as to correspond with the exterior of the entire casing produced when fluid metal is poured into the mold through the usual pas sage 15; the interior of theupper mold section being spaced apart from the core 8 and projection '1' a distance corresponding with the thickness of the wall. of theorising pro duced, as will be understood. The upper end of the core 8 is provided with a projection 16 in line with the projection 11 and which forms an opening for the reception of a second roller, ball or other bearing for the main shaft of the transmission gearing; and which projection engages the under side of the top wall of the interior of the upper mold section to steady the core and space its upper end from said top wall to thereby provide for a transverse end wall in the finished casing. The confronting interior surfaces at the upper ends of the mold section are 5 provided with recesses as shown in order to provide bosses for the formation of bearings for the shafts which comprise the change speed gear mechanism which is located with in the gear compartmentof the casing pro- 10 duced by the core 8, as shown in the drawing.

The projection 7 and the core 8 are provided with laterally extending portions or bosses at 17, 18, the surfaces of which are in substantial contact with the interior of the upper mold section when the mold sections are assembled, and the purpose of which is to provide openings in the finishedcasing which are closed by covers which support levers for operating the clutch, and for shifting the gears of the transmission gearing. These projections should extend toward the adjacent inner surface of the upper mold section as far as possible without actually contacting therewith, should the free ends of said member rub against the interior of the upper mold sect-ion during the assembling of the parts said projections, especially the projection 18, would be likely to be broken, being made'o-fgreen 3U sand as hereinbefore explained. In the finished casting thin tins of metalwill commonly extend partly or entirely across the openings formed as aforesaid, but these will be removed when the flanges about the openings are faced to provide a tight joint with the covers, or may be readily broken away from the wall surrounding the openings.

It will be appreciated from the foregoing description that my invention provides for the production of an integral single piece combined clutch and change speed gearing casing by the use of a flask comprising two parts only, and in a mold made entirely from green sand; thus simplifying the molding operations and materially reducing the floor space and quantity ofsand required for the production of a given nuiuber of casings. Thelabor cost of thecasings is also greatly reduced asno baked cores have to be provided, and the mold e1nployed is of simple form and one which .may be assembled with minimum expense The form and arrangement of the parts:

which make up the complete mold are such that they are not likely to be wrongly positioned during the assembling operation; and the form of mold herein has been found in. practice to he one in which the lossof cast ings due to improper closing of the mold m orto injury thereto during the assemblingr of the mold sections, is reduced to an E3} tremely small amount.

A further advantage securedin the use of my invention resides in the fact that the re suiting combined clutch and transmission bined clutch and change speed gear casing gearing casing is one having a smooth and symmetrical external surface, as there are no projections upon the outer wall thereof which, if present, (would interfere with the closing of the mold in the manner hereinbefore explained and as illustrated in Figure 5 of the drawing. I combined casing is one in which the number of surfaces whichhave to be finished by performing machine operations thereupon are reduced to a minimum and the cost of the finishing of the casing afterthe casting thereof is greatly reduced and the operrw tions necessary'to be performed thereon intterially simplified as no finished surfaces have to be provided between the clutch and thereupon, so that the same may be produced in a mold formed and assembled as herembefore GXPlZUHQCl, is regarded as an important feature of my invention, and as resulting in distinct advantages in the art" to which the same relates.

Having thus described and explained mv invention, 1 claim" and desire to secure by Letters Patent:

1. A sand mold for use in making a single piece casing having clutch and changespeed gearing chambers comprising a lower mold section having an, upwardly extending portion shaped to conform with the interior f the clutch chamber of the casing and which portion is provided with a recess in its upper end; a core supported by and above said portion and having a projectionextending downward and into said recess, and which core is spaced apart from'the upper end of said upwardly extending portion to provide a web separating the clutch and change speed gear chambers aforesaid from one another and the form of which core corresponds with that of the interior of said change speed gearingchamber; and an upper mold section" resting upon said lower section and the interior of which is shaped to correspond with the eizteriorof the comproduced in usingsaid mold, said upwardly extending portion and said core having laterally extending portions terminating in substantial contact with the inner surface of said upper mold section to thereby provide openings in thetinished casting.

2. A sand mold for use in making a cas-- ing having clutch and change speed gearing chambers comprisi-nga lower mold section- Furthermore, the

terior of said chamber; and an upper mold section resting upon said lower section and the interior of which is shaped to correspond with the exterior of the combined clutch.

and change speed gear casing produced in using said mold, said upwardly extending portion. and said core having laterally extending portions terminating in substantial contact with the inner surface of said upper mold section to thereby provide openings in the finished casting.

3. A sand mold for use in making a single piece casing having clutch and change speed gearing chambers comprising a lower mold section having an upwardly extending portion shaped to conform with the interior of the clutch chamber of the casing; a core supported by and above said portion, and the form of which corresponds with that of the interior of said chamber; and an upper mold section resting upon said lower section and the interior of which is shaped to correspond with the exterior of the combined clutch and change speed gear casing produced in using said mold, one of the parts aforesaid associated with said lower mold section having a laterally extending portion which terminates in substantial contact with the inner surface of said upper mold section to thereby provide an opening in the finished casting.

4:. A sand. mold for use in making a single piece casing having clutch and change speed gearing chambers comprising a lower mold section having an upwardly extending portion shaped to conform with the interior of the clutch chamber of the casing, and which portion is provided with a recess in its upper end; a core supported by and above said portion and having a projection extending downward and into said recess, and which core is spaced apart from the upper end of said upwar lly extending portion/co provide a web separating the clutch and change speed gear chambers aforesaid from one another and the form of which core corresponds with that of the interior of said change speed gearing chamber; and an up per mold section resting upon said lower section and the interior of which is shaped to correspond with the exterior of the combined clutch and change speed gear casing.

5. A sand mold for use in making a casing having clutch and change speed gearing chambers comprising a lower mold section having an upwardly extending portion shaped to conform with the interior of the clutch chamber of the casing; a core sup ported by and above said portion and spaced apart therefrom to provide a web separating the clutch and change speed gear chambers the exterior of the combined clutch and change speed gear casing.

6. A sand mold for use in making a single piece casing having clutch and change speed gearing chambers comprising a lower mold section having an upwardly extending portion shaped to conform with the interior of the clutch chamber of the casing; a core sup ported by and above said portion, and the form ofwhich corresponds with that of the interior-of said chamber; and an upper mold section resting upon said lower section and the interior of which is shaped to correspond with the exterior of the combined clutch and change speed gear casing produced in using said mold.

7. A sand mold for use in making a single piece casing having two separate and distinct chambers comprising a lower mold section having an upwardly extending portion shaped to conform with the interior of one of said chambers; a. core supported by and above said portion, and the form of which corresponds with that of the other of said chambers; and an upper mold section resting upon said lower section and the ex terior of which is shaped to correspond with the exterior of the entire casing made up of the chambers aforesaid, one of the parts aforesaid associated with said lower mold section having a laterally extending portion which terminates in substantial contact with the inner surface of said upper mold section when said sections are assembled.

8; A sand mold for use in making a single piece casing having twochambers separate from one another comprising a lower 'mold section having an upwardly extending portion shaped to conform with the interior of one of said chambers, and which portion is provided with a recess in its upper end; a core supported by and above said portion and having a projection extending downward into'said recess, and which core is spaced apart from the upper end of said upwardly extending portion to provide a web separating the two chambers of the casing from one another, and the form of which core corresponds with that of the interior of the other of said chambers; and an upper mold section resting upon said lower section and the interior of which is shaped to correspond with the exterior of the entire casing produced by the use of the mold.

9. A sand mold for use in making a caslOO having two chambers separate from one another comprising a lower mold section having an upwardly extending portion shaped to conform with the interior of one of the chambers aforesaid; a core supported by and above said portion and spaced apart therefrom to provide a web separating said two chambers from one another, and the form of which corresponds with that of the interior of the other of said chambers; and an upper mold section resting upon said lower section and the interior of which is shaped to correspond with the exterior of the entire casing produced in the use of said mold.

I 10;. A sand mold for use in making a single piece casing having two chambers separate from one another comprising a lower mold section having an upwardly extending portion shaped to conform with the in terior of one of said chambers; a core sup ported by and above said portion, and

shaped to conform with the interior of the other of said chambers; and an upper mold sect-ion resting upon said lower section and the interior of which is shaped to correspond with the exterior of the entire casing produced by the use of said mold. a

In testimony whereof I aflix'my signature.

ARTHUR A. BULL. 

